[Haskell-cafe] Re: monad subexpressions

[Claus Reinke]

> mytransaction = do {
>  x0 <- readTVar xvar0
>  x1 <- readTVar xvar1
>  :
>  xn <- readTVar xvarn
>  return $ foo x0 x1 .. xn
> }
> 
> Versus
> 
> mytransaction = return $ foo $(readTVar xvar0) $(readTVar xvar1) ..
> $(readTVar xvarn)

ah, a concrete example. but isn't that the typical use case for ap?

mytransaction = foo `liftM` r xvar0 `ap` r xvar1 ..
    where r = readTVar

claus